From 2b8db0ad29be4c12f2a1c5a209e15e5e14efc047 Mon Sep 17 00:00:00 2001
From: Dom Cobley <popcornmix@gmail.com>
Date: Thu, 27 Jan 2022 15:32:04 +0000
Subject: [PATCH] vc4/drm:plane: Make use of chroma siting parameter

Signed-off-by: Dom Cobley <popcornmix@gmail.com>
---
 drivers/gpu/drm/vc4/vc4_plane.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

--- a/drivers/gpu/drm/vc4/vc4_plane.c
+++ b/drivers/gpu/drm/vc4/vc4_plane.c
@@ -467,17 +467,18 @@ static void vc4_write_tpz(struct vc4_pla
 /* phase magnitude bits */
 #define PHASE_BITS 6
 
-static void vc4_write_ppf(struct vc4_plane_state *vc4_state, u32 src, u32 dst, u32 xy, int channel)
+static void vc4_write_ppf(struct vc4_plane_state *vc4_state, u32 src, u32 dst, u32 xy, int channel, int chroma_offset)
 {
 	u32 scale = src / dst;
 	s32 offset, offset2;
 	s32 phase;
 
 	/* Start the phase at 1/2 pixel from the 1st pixel at src_x.
-	   1/4 pixel for YUV. */
+	   1/4 pixel for YUV, plus the offset for chroma siting */
 	if (channel) {
 		/* the phase is relative to scale_src->x, so shift it for display list's x value */
 		offset = (xy & 0x1ffff) >> (16 - PHASE_BITS) >> 1;
+		offset -= chroma_offset >> (17 - PHASE_BITS);
 		offset += -(1 << PHASE_BITS >> 2);
 	} else {
 		/* the phase is relative to scale_src->x, so shift it for display list's x value */
@@ -563,13 +564,15 @@ static void vc4_write_scaling_parameters
 	/* Ch0 H-PPF Word 0: Scaling Parameters */
 	if (vc4_state->x_scaling[channel] == VC4_SCALING_PPF) {
 		vc4_write_ppf(vc4_state,
-			      vc4_state->src_w[channel], vc4_state->crtc_w, vc4_state->src_x, channel);
+			      vc4_state->src_w[channel], vc4_state->crtc_w, vc4_state->src_x, channel,
+			      state->chroma_siting_h);
 	}
 
 	/* Ch0 V-PPF Words 0-1: Scaling Parameters, Context */
 	if (vc4_state->y_scaling[channel] == VC4_SCALING_PPF) {
 		vc4_write_ppf(vc4_state,
-			      vc4_state->src_h[channel], vc4_state->crtc_h, vc4_state->src_y, channel);
+			      vc4_state->src_h[channel], vc4_state->crtc_h, vc4_state->src_y, channel,
+			      state->chroma_siting_v);
 		vc4_dlist_write(vc4_state, 0xc0c0c0c0);
 	}
 
@@ -1649,6 +1652,8 @@ struct drm_plane *vc4_plane_init(struct
 					  DRM_COLOR_YCBCR_BT709,
 					  DRM_COLOR_YCBCR_LIMITED_RANGE);
 
+	drm_plane_create_chroma_siting_properties(plane, 0, 0);
+
 	if (type == DRM_PLANE_TYPE_PRIMARY)
 		drm_plane_create_zpos_immutable_property(plane, 0);
 
